LOS ANGELES -- A physical education teacher at Carthay Center Elementary School outraged parents and upset students when he stripped naked on campus Friday and proceeded to chase nearby second-graders and fifth-graders.

"He was supposed to be helping them learn P.E., run around and have fun," one parent told CBS Los Angeles. "But he undressed and started chasing the kids while he was naked, and then the kids ducked and dodged, ran into some of the classrooms and got safe haven that way."

A video taken by a construction worker passing by captured the unidentified teacher putting his pants back on in the middle of the playground.

Parents were notified of the incident via robocall as well as a letter that was sent home with students.

"An individual began behaving in an unusual way, prompting us to contact law enforcement," the letter reads in part. "As a safety precaution, our school went on a brief lock-down while officers responded and took the individual into custody."

"All of the kids saw his private parts. Very embarrassing, very upset," said one parent.

While LAUSD officials say they cannot comment on the incident, they do say that the man was approved to be on campus and that he was a contracted employee.

Mental health counselors were made available to the children following the incident.

School police say they are continuing to investigate the man and are working on a case against him.